About 6 months ago or perhaps even longer - time rushes - we had a
discussion about bringing old files to live again.
There were various recipees, and in the meantime I have experimented
a little with these. I have tried citric acid, old pickle,
hydrocloric acid and other acids and aggressive media. I found out
that the recipee from Martin Niemeijer worked best for me, so here
Clean the files thoroughly with a steel brush and soak them in a hot
soda solution to degrease them. Rinse well in running water and dip
shortly in a mixture of 7 parts water, 3 parts sulphuric acid and 1
part nitric acid. (Do it outside and with your back to the wind, the
vapours are poisonous). After a few seconds in the acid mix remove
the files, clean them again under running water and dip in the soda
solution again to neutralize the acid and dry thoroughly. I have
found that filing in a piece of chalk after the drying helps to
prevent the files from rusting afterwards.
And then: Thanks Martin and happy filing to all.
Niels L=F8vschal, Rutsker, Denmark
phone (+45) 56 94 90 60